Jadpo is experimental and not ready for production. These docs follow the compiler's main branch as of 5 Nov 2026. What's built · Install 0.3.0

ReferenceErrors

Errors Logic · rule

`failure.outcome_duplicate_arm`

Outcome match handles a failure twice.

Area 3, Logic; not declinable; the next step is usually the agent's.

example

function duplicate_failure(key: LookupKey) -> LookupResult {    return match lookup(key) {        success(value) -> value        LookupMissing -> "missing"        LookupMissing -> "missing again"        LookupRefused -> "refused"    }}

jadpo checkcheck failed: 1 error, 2 files

error LookupMissing is handled twice

--> main.jadpo:5:9

  |4 |         LookupMissing -> "missing"  |         ------------- first matched here5 |         LookupMissing -> "missing again"  |         ^^^^^^^^^^^^^ matched again

reason: Each failure has one arm; the first takes every LookupMissing, so this one never runs.
next: Remove this arm, or merge its body into the first (agent)
rule: failure.outcome_duplicate_arm
help: https://jadpo.dev/docs/errors/failure.outcome_duplicate_arm

Markdown for agents: /docs/errors/failure.outcome_duplicate_arm.md.Built from Jadpo main at aee2e8f.